diff --git a/metagpt/utils/project_repo.py b/metagpt/utils/project_repo.py
index c7ddffb71..e2c7bb0e2 100644
--- a/metagpt/utils/project_repo.py
+++ b/metagpt/utils/project_repo.py
@@ -133,7 +133,7 @@ class ProjectRepo(FileRepository):
         code_files = self.with_src_path(path=git_workdir / git_workdir.name).srcs.all_files
         if not code_files:
             return False
-        return True
+        return bool(code_files)
 
     def with_src_path(self, path: str | Path) -> ProjectRepo:
         try:
diff --git a/tests/conftest.py b/tests/conftest.py
index f2379a833..efd782417 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -12,6 +12,7 @@ import logging
 import os
 import re
 import uuid
+from pathlib import Path
 from typing import Callable
 
 import aiohttp.web
@@ -270,3 +271,11 @@ def mermaid_mocker(aiohttp_mocker, mermaid_rsp_cache):
     aiohttp_mocker.rsp_cache = mermaid_rsp_cache
     aiohttp_mocker.check_funcs = check_funcs
     yield check_funcs
+
+
+@pytest.fixture
+def git_dir():
+    """Fixture to get the unittest directory."""
+    git_dir = Path(__file__).parent / f"unittest/{uuid.uuid4().hex}"
+    git_dir.mkdir(parents=True, exist_ok=True)
+    return git_dir
diff --git a/tests/metagpt/actions/test_summarize_code.py b/tests/metagpt/actions/test_summarize_code.py
index 3cfe7ca81..5e3057dee 100644
--- a/tests/metagpt/actions/test_summarize_code.py
+++ b/tests/metagpt/actions/test_summarize_code.py
@@ -6,8 +6,6 @@
 @File    : test_summarize_code.py
 @Modifiled By: mashenquan, 2023-12-6. Unit test for summarize_code.py
 """
-import uuid
-from pathlib import Path
 
 import pytest
 
@@ -178,10 +176,7 @@ class Snake:
 
 @pytest.mark.skip
 @pytest.mark.asyncio
-async def test_summarize_code(context):
-    git_dir = Path(__file__).parent / f"unittest/{uuid.uuid4().hex}"
-    git_dir.mkdir(parents=True, exist_ok=True)
-
+async def test_summarize_code(context, git_dir):
     context.src_workspace = context.git_repo.workdir / "src"
     await context.repo.docs.system_design.save(filename="1.json", content=DESIGN_CONTENT)
     await context.repo.docs.task.save(filename="1.json", content=TASK_CONTENT)
diff --git a/tests/metagpt/actions/test_write_code.py b/tests/metagpt/actions/test_write_code.py
index b5b6e4c52..1709e1f5b 100644
--- a/tests/metagpt/actions/test_write_code.py
+++ b/tests/metagpt/actions/test_write_code.py
@@ -7,7 +7,6 @@
 @Modifiled By: mashenquan, 2023-12-6. According to RFC 135
 """
 import json
-import uuid
 from pathlib import Path
 
 import pytest
@@ -25,6 +24,17 @@ from tests.data.incremental_dev_project.mock import (
 from tests.metagpt.actions.mock_markdown import TASKS_2, WRITE_CODE_PROMPT_SAMPLE
 
 
+def setup_inc_workdir(context, inc: bool = False):
+    """setup incremental workdir for testing"""
+    context.src_workspace = context.git_repo.workdir / "src"
+    if inc:
+        context.config.inc = inc
+        context.repo.old_workspace = context.repo.git_repo.workdir / "old"
+        context.config.project_path = "old"
+
+    return context
+
+
 @pytest.mark.asyncio
 async def test_write_code(context):
     # Prerequisites
@@ -89,13 +99,9 @@ async def test_write_code_deps(context):
 
 
 @pytest.mark.asyncio
-async def test_write_refined_code(context):
+async def test_write_refined_code(context, git_dir):
     # Prerequisites
-    git_dir = Path(__file__).parent / f"unittest/{uuid.uuid4().hex}"
-    git_dir.mkdir(parents=True, exist_ok=True)
-    context.config.inc = True
-
-    context.src_workspace = context.git_repo.workdir / "src"
+    context = setup_inc_workdir(context, inc=True)
     await context.repo.docs.system_design.save(filename="1.json", content=json.dumps(REFINED_DESIGN_JSON))
     await context.repo.docs.task.save(filename="1.json", content=json.dumps(REFINED_TASK_JSON))
     await context.repo.docs.code_plan_and_change.save(
@@ -103,7 +109,6 @@ async def test_write_refined_code(context):
     )
 
     # old_workspace contains the legacy code
-    context.repo.old_workspace = context.repo.git_repo.workdir / "old"
     await context.repo.with_src_path(context.repo.old_workspace).srcs.save(
         filename="game.py", content=CodeParser.parse_code(block="", text=REFINED_CODE_INPUT_SAMPLE)
     )
@@ -126,8 +131,7 @@ async def test_write_refined_code(context):
 @pytest.mark.asyncio
 async def test_get_codes(context):
     # Prerequisites
-    context.src_workspace = context.git_repo.workdir / "src"
-    context.repo.old_workspace = context.repo.git_repo.workdir / "old"
+    context = setup_inc_workdir(context, inc=True)
     for filename in ["game.py", "ui.py"]:
         await context.repo.with_src_path(context.src_workspace).srcs.save(
             filename=filename, content=f"# {filename}\nnew code ..."
diff --git a/tests/metagpt/actions/test_write_code_plan_and_change_an.py b/tests/metagpt/actions/test_write_code_plan_and_change_an.py
index f564a677b..5c262b4b7 100644
--- a/tests/metagpt/actions/test_write_code_plan_and_change_an.py
+++ b/tests/metagpt/actions/test_write_code_plan_and_change_an.py
@@ -6,8 +6,6 @@
 @File    : test_write_code_plan_and_change_an.py
 """
 import json
-import uuid
-from pathlib import Path
 
 import pytest
 from openai._models import BaseModel
@@ -32,6 +30,7 @@ from tests.data.incremental_dev_project.mock import (
     REFINED_TASK_JSON,
     TASK_SAMPLE,
 )
+from tests.metagpt.actions.test_write_code import setup_inc_workdir
 
 
 def mock_code_plan_and_change():
@@ -39,19 +38,12 @@ def mock_code_plan_and_change():
 
 
 @pytest.mark.asyncio
-async def test_write_code_plan_and_change_an(mocker, context):
-    # Prerequisites
-    git_dir = Path(__file__).parent / f"unittest/{uuid.uuid4().hex}"
-    git_dir.mkdir(parents=True, exist_ok=True)
-    context.config.inc = True
+async def test_write_code_plan_and_change_an(mocker, context, git_dir):
+    context = setup_inc_workdir(context, inc=True)
+    await context.repo.docs.prd.save(filename="2.json", content=json.dumps(REFINED_PRD_JSON))
+    await context.repo.docs.system_design.save(filename="2.json", content=json.dumps(REFINED_DESIGN_JSON))
+    await context.repo.docs.task.save(filename="2.json", content=json.dumps(REFINED_TASK_JSON))
 
-    context.src_workspace = context.git_repo.workdir / "src"
-    await context.repo.docs.prd.save(filename="1.json", content=json.dumps(REFINED_PRD_JSON))
-    await context.repo.docs.system_design.save(filename="1.json", content=json.dumps(REFINED_DESIGN_JSON))
-    await context.repo.docs.task.save(filename="1.json", content=json.dumps(REFINED_TASK_JSON))
-
-    context.config.project_path = "old"
-    context.repo.old_workspace = context.repo.git_repo.workdir / "old"
     await context.repo.with_src_path(context.repo.old_workspace).srcs.save(
         filename="game.py", content=CodeParser.parse_code(block="", text=REFINED_CODE_INPUT_SAMPLE)
     )
@@ -67,9 +59,9 @@ async def test_write_code_plan_and_change_an(mocker, context):
 
     code_plan_and_change_context = CodePlanAndChangeContext(
         requirement="New requirement",
-        prd_filename="1.json",
-        design_filename="1.json",
-        task_filename="1.json",
+        prd_filename="2.json",
+        design_filename="2.json",
+        task_filename="2.json",
     )
     node = await WriteCodePlanAndChange(i_context=code_plan_and_change_context, context=context).run()
 
@@ -96,12 +88,8 @@ async def test_refine_code(mocker):
 
 
 @pytest.mark.asyncio
-async def test_get_old_code(context):
-    git_dir = Path(__file__).parent / f"unittest/{uuid.uuid4().hex}"
-    git_dir.mkdir(parents=True, exist_ok=True)
-
-    context.config.project_path = "old"
-    context.repo.old_workspace = context.repo.git_repo.workdir / "old"
+async def test_get_old_code(context, git_dir):
+    context = setup_inc_workdir(context, inc=True)
     await context.repo.with_src_path(context.repo.old_workspace).srcs.save(
         filename="game.py", content=REFINED_CODE_INPUT_SAMPLE
     )
diff --git a/tests/metagpt/actions/test_write_prd.py b/tests/metagpt/actions/test_write_prd.py
index 0a2739975..43aa336b7 100644
--- a/tests/metagpt/actions/test_write_prd.py
+++ b/tests/metagpt/actions/test_write_prd.py
@@ -6,8 +6,6 @@
 @File    : test_write_prd.py
 @Modified By: mashenquan, 2023-11-1. According to Chapter 2.2.1 and 2.2.2 of RFC 116, replace `handle` with `run`.
 """
-import uuid
-from pathlib import Path
 
 import pytest
 
@@ -19,6 +17,7 @@ from metagpt.roles.role import RoleReactMode
 from metagpt.schema import Message
 from metagpt.utils.common import any_to_str
 from tests.data.incremental_dev_project.mock import NEW_REQUIREMENT_SAMPLE, PRD_SAMPLE
+from tests.metagpt.actions.test_write_code import setup_inc_workdir
 
 
 @pytest.mark.asyncio
@@ -39,11 +38,8 @@ async def test_write_prd(new_filename, context):
 
 
 @pytest.mark.asyncio
-async def test_write_prd_inc(new_filename, context):
-    git_dir = Path(__file__).parent / f"unittest/{uuid.uuid4().hex}"
-    git_dir.mkdir(parents=True, exist_ok=True)
-
-    context.src_workspace = context.git_repo.workdir / "src"
+async def test_write_prd_inc(new_filename, context, git_dir):
+    context = setup_inc_workdir(context, inc=True)
     await context.repo.docs.prd.save("1.txt", PRD_SAMPLE)
     await context.repo.docs.save(filename=REQUIREMENT_FILENAME, content=NEW_REQUIREMENT_SAMPLE)
 
@@ -59,10 +55,7 @@ async def test_write_prd_inc(new_filename, context):
 
 
 @pytest.mark.asyncio
-async def test_fix_debug(new_filename, context):
-    git_dir = Path(__file__).parent / f"unittest/{uuid.uuid4().hex}"
-    git_dir.mkdir(parents=True, exist_ok=True)
-
+async def test_fix_debug(new_filename, context, git_dir):
     context.src_workspace = context.git_repo.workdir / context.git_repo.workdir.name
 
     await context.repo.with_src_path(context.src_workspace).srcs.save(